Question

$4$ charges are placed each at a distance '$a$' from origin. The dipole moment of configuration is:

• A. $2qa\hat{j}$
• B. $3qa\hat{j}$
• C. $2aq[\hat{i}+\hat{j}]$
• D. $2aq(\hat{i}-\hat{j})$

Answer 1

The correct option is A $2qa\hat{j}$

Dipole moment for the given configuration is $\overrightarrow{p}=(-2q)\left(a\hat{i}\right)+\left(3q\right)\left(a\hat{j}\right)+(-2q)(-a\hat{i})+\left(q\right)(-a\hat{j})=2qa\hat{j}$
Ans:(A)